1. Field of the Invention
The present invention relates to a decrease in dust emission of a ferrite sintered magnet and a method for producing the ferrite sintered magnet. The invention also relates to a decrease in dirt of a motor.
2. Description of the Related Art
Ferrite sintered magnets are widely used for motors and the like mounted in household electric appliances, automobiles, and the like. Japanese Patent Application Laid-Open No 10-125519 describes a technique in which a glass glaze is applied to the surface of a ferrite sintered magnet and baked.
Ferrite sintered magnets produced in a general process come in contact with each other to cause friction during transport. As a result, magnet dust is generated and the surface of the ferrite sintered magnets may be tarnished. In order to suppress the generation of the dust and the tarnish of the ferrite sintered magnet, a work of individually packing the ferrite magnets, and the like are required before the transport, and thus a packing cost is increased. Further, when the ferrite sintered magnets are assembled into various machines, the ferrite sintered magnets come in contact with a fastening tool and the surface of the ferrite sintered magnets is rubbed with the tool. As a result, dust is generated. For example, when the ferrite sintered magnets are inserted into and attached to a case of a motor, the ferrite sintered magnets are rubbed against the case to generate dust. The motor gets dirty by the dust. The technique in Patent Literature 1 aims to prevent dirt caused by generated magnetic powder. However, when after a general process of producing a ferrite sintered magnet, a glaze application process and a baking process are performed as the technique in Patent Literature 1, the number of processes is increased, and a material cost is also increased. Therefore, a production cost is increased.